The present invention relates to a mechanism for automatic inking at predetermined points on a paperboard printing machine.
For a traditional paperboard press, ink is applied to the rollers of the press by an operator using an ink brush. Since the rollers rotate at high speed, the operator has to stand beside the rollers when applying ink to the rollers. Accidents frequently happen when an ink brush or even the hand of operator is unexpectedly clamped by the rotating rollers. Apart from the accidents, disadvantages from manual inking based on visual judgement, such as variable amount of ink applied, unevenly and untimely applied ink, error in inking positions, missed application of ink, etc. might very possibly cause the resulted printing on the paperboard to be smudgy, unclear, poor effect, etc.
Articles to be printed on a paperboard press are usually unfolded paperboard used to making cartons. The paperboard (which is generally the so-called corrugated board) is usually printed with what we commonly refer to as shipping marks. The marks can be further classified into a master mark which is larger in size and is shown on the front side of a carton for showing the description of the article contained therein or trademark thereof, and a side mark which is smaller in size and is shown on side and/or bottom faces of a carton for showing address and/or phone number of the consignee, or other descriptive letterings. Usually, amount of ink used relates to the size of printed marks or letters. For the master marks in which larger letters are used, ink of higher consistency and richer amount is required, and, for the side marks, less ink is required.
To eliminate the drawbacks existed in the traditional manual-inking press, automatic inking printing machines are developed. However, such conventional automatic inking printing machines would usually cause additional loss or consumption of ink because the entire surface of the roller must be applied with ink; besides, amount of ink applied to print the paperboard is the same for every part of the board, that is, the ink consistency for printing master marks and for side marks is the same, and therefore, not every marks or letters may have desired degree of clearness, that is, smaller letters would be smudged if the larger letters got the desired clearness, and reversely, the larger letters might be too light if the smaller letters got the desired clearness.
In view of these disadvantages, it is necessary to have another improved automatic inking mechanism which may evenly supply adequate amount of ink to the roller to meet different ink consistency required by printed marks or letters in different sizes lest ink should be unnecessarily wasted.